Examples of experimental Raman spectra (symbols) for the MQW detected after a treatment of the samples with a laser radiation at with power values (a) and (b). The Raman spectra were fitted with peaks related to a-Si, Si-clusters, and Si-nc. The cumulative and individual fitting curves are also indicated in the figure.
The evolution of the Raman spectra for the MQW with the variation in the laser power, at . The spectra are shifted on vertical axis for clarity of presentation. The values of in mW and the magnification factors for the signal amplitude (in brackets) are given above each spectrum. The dotted line shows position of the marker peak (Hg) used for the precise calibration of the wave numbers.
The dependence of the integrated intensities of Raman peaks from various Si phases on at for the MQW. A cumulative signal from all Si related phases is presented by and is a fraction of Si-nc signal, i.e., . The attribution of the symbols is indicated in the figure. The curves are shown to guide the eye. Note a difference between the optimal laser power values for maximal signal, and the optimal power for maximal Si-nc fraction, .
(a) Variations in the Si-nc Raman peak parameters, i.e., the FWHM and the spectral position of the maximal intensity, , with change in at for the MQW. (b) Dimensions of Si-nc inclusions, and average strain in the samples, estimated from data in (a). In (b): positive corresponds to a compressive strain, while negative to a tensile strain. The attribution of the symbols is presented in the figure. The curves are shown to guide the eye.
(a) The dependence of the optimal laser radiation power, and (b) the normalized Si-nc related Raman signal intensity, detected after the treatment with such power on the wavelength of laser radiation, for the MQW sample. The normalized part of absorbed radiation for single, 10 nm thick a-Si layer, is presented in (a) by a dashed curve. The spectral dependence for an efficiency of crystallization, estimated using Eq. (1) and that of are also presented in (b). The attribution of the symbols is presented in the figure. The curves are shown to guide the eye.
(a) The dependence of fractions of a-Si, Si-nc and Si-cluster phases and (b) of average dimensions of Si-nc crystallites and the average tensile strain in the system from the duration of the light treatment of the MQW with at . The attribution of the symbols is indicated in the figure. The curves are shown to guide the eye.
The time dependence of the temperature of the sample surface under the laser irradiation for a-Si and c-Si containing MQW on the quartz substrate estimated using Eq. (2) and the data from Table I. Parameters of laser radiation and attributions of the lines are presented in the figure.
Values of parameters of a-Si, c-Si, and quartz used for the estimations. The related references are presented after each parameter label.
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